Question

In the given figure P is 300 km eastward of O and Q is 400 kms North of Q, R is exactly in the middle of Q and P The distance between Q and R is ______________.

• A. 250 kms
• B. $250\sqrt{2}kms$
• C. 300 kms
• D. 350 kms
• E. None of these

Answer 1

The correct option is A 250 kms

PQ = OP2+OQ2−−−−−−−−−−√OP2+OQ2
=(300)2+(400)2−−−−−−−−−−−−√=1002(32+42)−−−−−−−−−−−√(300)2+(400)2=1002(32+42)
=1002×52−−−−−−−−√=(100×5)=1002×52=(100×5) i.e. 500 km
R being in the midway of PQ so QR = 250 kms